To evaluate the immunologic consequence of bilateral vasectomy, determine the incidence, quantity, time of onset, and persistence of humoral antisperm antibody by the indirect immunofluorescence technique; and determine the existence of cell-mediated immune response to sperm by in vitro techniques including the release of macrophage migration inhibition factor and augmented DNA synthesis by sensitized lymphocytes in the presence of sperm antigens in patients following bilateral vasectomy. The nature of the antisperm antibody with respect to immunoglobulin class and organ antigenic specificity will be defined. The immunopathologic consequence of bilateral vasectomy will be determined in experimental animals that are making an immune response to sperm; e.g., in guinea pigs with bilateral vasectomy and in rats with alpha-chlorhydrin induced sperm granuloma.